US2182407A - Motor vehicle power transmission - Google Patents

Description

Dec. 5, 1939. A. .1. PHELAN ET AL 2,182,407

MOTOR VEHICLE POWER TRANSMISSION Filed May 17, 1939 lNVENTOR P&el.4)z, 5

Patented Dec. 5, 1939 UNITED STATES PATENT OFFICE MOTOR VEHICLE POWER TRANSMISSION' Delaware Application May 17, 1939, Serial No. 274,240

4 Claims.

This invention relates to motor vehicles and refers more particularly to improvements in the power transmission for driving motor vehicles.

This application is a continuation in part of 5 our application Serial No. 228,296, filed September 3, 1938.

One object of our invention is to provide an improved system of power transmission of the type embodying a fluid couping of the kinetic type which transmits the drive from the engine to the vehicle under control of a clutch operable to release or establish the drive from the fluid coupling. In practice the clutch is preferably located in the drive between the fluid coupling and a speed ratio changing transmission of any suitable type.

Power transmission systems of the aforesaid type have been proposed but difiiculty has been experienced in providing desired relationship of the parts from standpoints of adequate bearing supports, freedom from binding of the various parts, and arranging the parts so that they do not require more room than is conveniently available for the assembly as a whole. We have provided a power transmission system which, among other things, overcomes the aforesaid difliculties and is especially adapted for commercial manufacture and use in motor vehicle drives.

A further object of our invention is to provide an improved arrangement of fluid coupling and clutch so related to the engine driving shaft and the transmission that the coupling and clutch will not bind at the various supporting bearings and will not result in an out of balance condition even where minor misalignment of the crankshaft and transmission bearings occurs. It is highly important to provide and preserve a very accurate running balance for the fluid coupling runner, which presents a large mass when con- 40 sidered with the working fluid carried thereby,

and great difliculty has been experienced in commercial uses of fluid couplings and clutches to provide and maintain a running balance of these parts within the ordinary tolerances required for alignment of the support bearings.

problem is aggravated by the use of a clutch behind the fluid coupling as this clutch, preferably of the usual dry-plate commercial type, is quite massive and introduces further problems of deflections in the supporting means, out of balance tendencies, and other difilculties.

We have provided an arrangement which overcomes the aforesaid difficulties and makes possible the use commercially of fluid coupling and clutch installations in motor vehicles.

. automobiles.

drawing:

The,

In carrying out our invention we mount the coupling runner and the relatively massive driving parts of the clutch on the transmission input shaft which is supported at its front end on the crankshaft by a ball bearing and at its rear end 5 on the-transmission by a ball bearing. These ball bearings act as universal-joints to accommodate misalignment of the crankshaft and transmission within the limits customarily experienced in ordinary commercial practice in assembling The transmission input shaft is free to tilt slightly without binding at any point and as the coupling runner and clutch, including the driven clutch disk, are all mounted and centered on the input shaft their desired balanced 15 relationship is preserved even for the slight. misalignment and tilting referred to above. T

In order to even further obtain and preserve great accuracy in the balance of the coupling runner, the latter is preferably formed with-a relatively long hub whose front end is directly supported by the crankshaft ball bearing and whose rear end carries the driving parts of the clutch. Thus, the transmission input shaft is relieved of a large amount of the coupling runner load thereby avoiding objectionable shaft deflections and whip" and the runner balance is facilitated by being centered directly at the front ball bearing which also acts as a thrust bearing for th runner in opposite axial directions.

Further objects andadvaptages of our invention will be more apparent as this specification progresses with reference to one illustrative embodiment of our invention. In the accompanying F'ip. 1 is a side elevational view of the power transmitting assembly.

Fig. 2 is a longitudinal sectional elevational view of the fluid coupling and clutch of the Fig. 1 assembly.

Referring to the drawing, reference numeral Ill represents the forward end of the engine crankshaft which is the driving shaft for the power transmission system, the crankshaft being 45 adapted to transmit the drive through a fluid coupling A of the kinetic type. The fluid coupling is arranged to transmit the drive through a clutch B which, for the most part, may be of any suitable well known type for transmitting the 50 drive to the transmission input shaft II which preferably leads to any suitable type of speed ratio changing mechanism or, if preferred, the input shaft Il may be arranged to drive the usual ground wheels (not shown) of the vehicle 55 without passing through any selectively operable speed ratio changing mechanism.

In the illustration the input shaft II is adapted to drive the speed ratio changing mechanism C of any suitable type and the drive from transmission C may pass through an auxiliary transmission D which, when employed, is preferably in the form of an overdrive mechanism of the usual well known type. The drive from the mechanism D passes in the usual manner to the driving ground wheels of the vehicle.

Secured to the rear end of crankshaft III by the fasteners l2, we have provided a supporting journalling member l3 on which is drivingly mounted the impeller structure M of fluid coupling A, this impeller having the usual radially extending vanes l5 for directing the fluid medium by the action of centrifugal force toward corresponding vanes l6 of the runner structure |1 whereby to transmit the drive from the impeller to the runner in the well known manner. The impeller |4 extends rearwardly and inwardly through the shrouding or cover portion Hi thereby enclosing the runner l1 and in order to seal the'fluid coupling against escape of the fluid we have provided the sealing structure I 9 between,

the shrouding l8 and the hollow hub on which the runner I1 is drivingly mounted, it being understood that the runner is adapted to rotate relative to the impeller and its shrouding l8. The sealing structure l9 rotates with the shrouding l8 and is provided with a sealing ring 2| which rotatably engages a companion sealing member 22 carried by the hollow hub 20 in order to accommodate this relative rotation between the impeller and runner while preventing the escape of fluidfrom the coupling A. The arrangement is such that hub 20 along with shaft may tilt freely without binding at shrouding |8 by reason of the clearance at l9.

The support member |3 has a portion 23 thereof which extends rearwardly within the fluid coupling and carries an anti-friction ball bearing 24 providing a journal support for the forwardly extending end of the hub 20 which extends forwardly within the portion 23 of the supporting member l3. The ball bearing 24 also acts as a thrust bearing preventing axial displacement of hub 20 in either direction and absorbing axial thrusts from the runner H. The forward end of hub 20 is closed by a plug 25 for preventing escape of the fluid from the coupling at this point. Located preferably concentrically within the bearing 24, we have provided a second bearing 26 preferably of the anti-friction roll type for journallingthe forward end of the input shaft Ii, the rear-end of this shaft being supported by a third bearing 21 of the anti-friction ball type carried by the speed ratio transmission C. The rear end of the input shaft may have the usual input pinion or gear 28 for transmitting the drive to the transmission mechanism C;

The hollow hub 20 extends rearwardly preferably with clearance with respect to the shrouding l8 so that hub 20 may tilt slightly without binding at the shrouding, the rear end of the hollow hub being journalled by a fourth bearing 29 preferably of a type similar to the aforesaid bearing 26. Fixed to the rear end portion of the hollow hub 20 so as to surround ,,the bearing 29 we have provided the flywheel-like driving member 30 of the clutch B which may be of the usual well known friction type carrying the pressure plate 3| loaded by springs 32 for establishing the drive between the relatively massive clutch driving members 30' and 3| and the relatively light weight friction disc 33 which provides the driven member of the clutch B.

The driven disc 33 is carried by a hub 34 drivingly secured to the input shaft adjacent the rear end of the hollow hub 20. Any suitable means may be arranged to disengage the clutch B as for example the throw-out mechanism 35 adapted to operate through the usual levers 36 to move the pressure'plate 3| rearwardly against the action of the springs 32. The throw-out mechanism 35 is slidable on a forwardly extending hollow sleeve 31 which is rigidly fixed by fasteners 38 to the casing of transmission C so that the hollow sleeve projects cantilever-like from the transmission casing where it derives its sole support. The input shaft H is free to tilt slightly by a universal action at roller bearings 24 and 21 to compensate without binding for any minor misalignment between crankshaft l0 and transmission C. Therefore, in order to realize such free tilting action of the input shaft II it is necessary that shaft ll be free from transversely fixed restraint at any point between bearings 24 and 21. The sleeve 31 is therefore provided with a clearance 39 with shaft II, this clearance being greater as at 40 adjacent the forward end of the sleeve 31 to insure against binding of the shaft at the regions more remote from the point of universal support at bearing 21. We have found that a clearance tolerance of approximately from .011 to .016 of an inch is adequate for the clearance 39 under average conditions, in order to realize the benefits of our invention. If desired, the clearance 39 may have an oil packing associated therewith but as the sleeve 31 does not journal the shaft I it does not require lubrication. If desired the sleeve 31 may have an internal thread 4| of such hand that the rotation of shaft II will tend to urge any oil, which may accumulate thereon, back toward bearing 21.

In the operation of the mechanism the crankshaft l0 and the impeller structure l4 rotate in unison causing the fluid in thecoupling A to rotate the runner l1 thereby driving the hollow hub 20 and the driving member 30 of clutch B. When this clutch is engaged, as illustrated, the drive passes through the driven disc 33 to the input shaft II and thence through the mechanisms C and D to drive the vehicle. The fluid coupling A will ordinarily provide suflicient inherent slip at low speeds so that when the engine is idling the clutch B may be left engaged and the mechanisms C and D in driving condition without any drive passing from the crankshaft III to the runner structure l1 and hollow hub 20. However, in order to facilitate manipulation of the mechanism C for changing gears therein, as when the car is being driven, the clutch B is preferably disengaged during the time of speed ratio changes in order to facilitate such changes without tendency to clash the gears. Also at any time when it is desired to interrupt the drive from the crankshaft III to the driving wheels of the vehicle the driver may bring this about by disengaging the clutch B by operation of. the throw as well as providing additional advantages. While the forward end of the hollow hub 20 may, if preferred, be rotatably supported directly by the crankshaft I 0, we preferably support this hub by the crankshaft through the medium of the support member I3.

By reason of our novel arrangement of parts including the various bearings, the parts of the power transmission illustrated in Fig. 2 have improved stability without tendency toward objectionable vibration and misalignment of the parts. The input shaft II, for example, is advantageously arranged in that it extends between the transmission C and crankshaft [0 being journalled at the latter location by the concentrically arranged bearings 25 and 24 through the medium of the forward portion of the hollow hub 20 which, in turn, is given improved stability by reason of the widely spaced bearings 26 and 29 on the input shaft ll.

Furthermore, minor misalignments between the I centered on shaft H, tilting of the latter does not throw the parts carried thereby out of balance. In addition, runner i6 is not fully supported by shaft Ii because of the hub 20 being directly journalled at its forward end on the crankshaft at bearing 24,'thereby relieving shaft H of deflections which might well be objectionable.

We do not limit our invention, in the broader aspects thereof, to any particular combination and arrangement of parts such as shown and described for illustrative purposes since various modifications will be apparent from the teachings of our invention and scope thereof as defined in the appended claims.

We claim:

1. In a motor vehicle power transmission system having a driving shaft and a change speed transmission having an input shaft, a hydraulic coupling of the kinetic type having an impeller structure drivingly connected to the driving shaft and a runner structure, said runner structure having a hollow hub, a bearing of the anti-friction ball type carried by the driving shaft and journalling the forward end of said hub, a second bearing journalling the forward end of the input shaft within the forward end of said hub, a third bearing of the anti-friction ball tyne carried by said change speed transmission and journalling the rear end of the input shaft, a clutch disposed at the rear of said hydraulic coupling, said clutch comprising a driving clutch member drivingly mounted on the rear end of said hub and a driven clutch member drivingly mounted on the input shaft at a point between said second and third bearings, and a fourth bearing journalling the rear end of said hub on said input shaft, said second and fourth bearings maintainng said runner structure and said driving clutch member centered on said input shaft, said first and third bearings providing the entire support for said input shaft and said hollow hub and being 'so constructed and arranged as to accommodate universal tilting of said input shaft together with said runner structure and said clutch as a unit to compensate for minor misal gnment between the driving shaft and transmission.

2. In a motor vehicle power transmission system having a driving shaft and a change speed transmission having an input shaft, a hydraulic coupling of the kinetic type having an impeller structure, a support member attached to the rear end of the driving shaft for drivingly mounting said impeller, said support member having a hollow journalling portion extending rearwardly of the driving shaft, said hydraulic coupling having a runner structure provided with a hollow hub, a bearing of the anti-friction ball type carried within the hollow journalling portion of said support member and journalling the forward end of said hub, a second bearing journalling the forward end of the input shaft within the forward end of said hub, a third bearing of the antifriction ball type carried by said change speed transmission and journalling the rear end of the input shaft, a clutch disposed at the rear of said hydraulic coupling, said clutch comprising a driving clutch member drivingly mounted on the rear end of said hub and a driven clutch member drivingly mounted on the input shaft at a point between said second and third bearings, and a fourth bearing journalling the rear end of said hub on said input shaft, said input shaft together with said runner structure and said clutch being free for limited displacement thereof as a unit to compensate for misalignment of the driving shaft and transmission.

3. In a motor vehicle power transmission system having a driving shaft and a change speed transmission having an'input shaft, a hydraulic coupling of the kinetic type having an impeller structure drivingly connected to the driving shaft and a runnerstructure, said runner structure having a hollow hub, a bearing of the anti-friction ball type carried by the driving shaft and journalling the forward end of said hub, a second bearing disposed concentrically within the first said bearing and journalling the forward end of the input shaft within the forward end of said hub, a third bearing of the anti-friction ball type carried by said change speed transmission and journalling the rear end of the input shaft, a friction clutch disposed at the rear of said hydraulic coupling, said clutch comprising a drivingflywheel clutch member drivingly mounted on the rear end of said hub and a driven friction plate clutch member drivingly mounted on the input shaft at a point between said second and third bearings, and a fourth bearing disposed forwardly adjacent said driven clutch member and journalling the rear end of said hub on said input shaft, said input shaft together with said runner structure and said clutch being free for limited tilting as a unit accommodated by the first and third said bearings to compensate for misalignment of the driving shaft and transmission.

4. In a motor vehicle power transmission system having a driving crankshaft, a change speed transmission spaced rearwardly from said crankshaft, an input shaft for said change speed transmission, means journalling the rear end of said input shaft on said change speed transmission accommodating limited universal tilting of the driving shaft relative to the transmission, a hydraulic coupling of the kinetic type comprising an impeller connected to the crankshaft and a run ner provided with a hollow hub, means journalling the front end of said hub on said crankshaft accommodating limited universal tilting of the hub relative to the crankshaft, means journalling the front end of said input shaft in the front end of said hub, clutch means operably connecting them-ear end of said hub withsaid input shaft at a point intermediate said front end and rear end Journail ng means for said input shaft, and means journalling the rear end of said hub on said input shaft forwardly adjacent said intermediate point, said input shaft together with said runner and clutch being free to tilt as a unit to compensate for misalignment of the driving shaft and transmission.

ARTHUR J. PHELAN. HUBERT S. PHELAN.

Images